The last sticky became very unorganised and has filled up with a lot of spam, so I've decided to recreate this. Credit goes to throwthisaway who started the original topic and who I stole much of the links, layout and text from (albeit reworded).
If you have suggestions or additions, including links or addendums, feel free to PM me and I'll make sure to add them if they prove to be useful.
Windows XP (Home/Professional)
Here's a little checklist to look at if you ever notice that your computer's running a little slow.
The largest problem often faced by PC users when their machines slow down is caused by the infection of the computer by malware. Essentially this is any software that has malicious intent in order to slow down or damage your computer. This is very easy to acquire in today's world, just by downloading any sort of executable program (.exe) that you're not sure of can actually be hiding spyware or other malicious software even if it claims to perform what it does. This is why you have to be able to use your head and not download or install anything that seems suspicious or fake. Even by not installing Windows security patches (which is a must) you can be open to a host of exploits that can advantage of errors in Windows and cause harm to your computer.
Step 1 - First of all, update your virus definitions. This can be found in the update area of the software and normally happens automatically. For more elaborate viruses you may have to boot into Safe Mode and then run the anti-virus software. Depending on how bad the infection is and how much the software can find, this can take a while, so you might want to leave your PC and go do something else.
Step 2 - If you've noticed this slowing down recently, then the cause might be a piece of software that you've installed recently. You can often look at the Windows Restore Points to find out what you installed and when and check to see if any coincide with the slowing down. Once you think you've found the cause, completely uninstall the software, and it's also advised to run an anti-virus and anti-spyware check at this point to see if there was anything malicious behind it. For prevention, don't recklessly download software you're not sure about - Google can be invaluable in finding out if others have had the same problem with the software or if it's known to be malware.
Step 3 - While you're in the aforementioned Safe Mode, you can run a few anti-spyware programs to remove as much as you can if there have been infections; each company has a different set of definitions of what they include as spyware and so each company's application removes different things. Usually there may just be a few things that one misses out. However it's also important to note that running all of these on a continuous basis (especially if they have real-time protection modes) can sometimes interfere with each other and slow down the computer while they're running. You should also note that you should always have only ONE anti-virus program installed on your computer at any one time, as problems can occur when they conflict with each other. Spyware scanners are usually less intense on the computer and much simpler pieces of software so you don't run the same risk, even though it's still possible for them to interfere.
Step 4 - Another problem could lie within the automatic application startups. If you're more of an advanced user, push the Windows key and R simultaneously (or go to Start > Run manually) and type "services.msc" without the quotes. Take note of the location of the files and the application name. It's best not to click anything you're not sure about so you don't do anything wrong. You can, however, instead use a utility called Windows Startup Inspector, which is a more 'intense' alternative to the "services.msc" command.
Extra (Optional) Steps To Take
Often once people have been using a computer for a few years or a while software and files build up. It's very helpful to clean out applications that you don't use anymore or have no need for. You can go to the Add/Remove Programs section of the Control Panel to easily find out what's installed and click to remove them. This can help to remove unnecessary files and give more space for the computer (and you) to work with. Going through your own files can also be helpful, delete unused stuff like zip files you've unzipped and store elsewhere, that odd text file you made for your shopping list, that printer you don't have anymore, etc; It's all up to your discretion and what you don't need.
 Anti-Virus Scanners
- Avast Free
- AVG Free (at the bottom of the page)
- BitDefender Free
NB: Kaspersky and NOD32 are not free - the rest are.
 Spyware Removal
- Microsoft Windows Defender
- Ad-Aware Free
- Spybot: Search & Destroy
- SpywareBlaster and SpywareGuard (together make a strong package).
 Online Virus / Trojan Scanners
NB: Online scanners are never as good as actual software packages and it's always best to run a decent anti-virus software that stops viruses coming into the system. These, however, are still a good tool and can be quite effective if your antivirus software is compromised or doesn't seem to be working.
- HouseCall - Java (Does not require IE, it uses Java instead of ActiveX)
- Kephyr PopUp Killer
- PC PitStop
- Spyware Guide
- Spyware Info
- Spy Audit (Does not remove/add any files to your system)
- Windows Security
Post edited at 4:33 pm on Aug. 9, 2009 by polio